Apparatus for manufacture of phonograph records



June 19,- 1962 KAZUICHI NlSHlOKA ETAL 3,039,139

APPARATUS FOR MANUFACTURE OF PHONOGRAPH RECORDS Filed May 21, 1958 f I I 2 1 v s mad/cw Mal/0K5, 5 2 05 new,

TMU lV/SIl/OKH United States Patent 3,039,139 APPARATUS FOR MANUFACTURE OF PHONOGRAPH RECORDS Kazuichi Nishioka, 18 Imazu Yamanaka-cho, Kazuo Adachi, 4-88 Kami-Koshien, and Tom Nishioka, 18

Imazu Yamanaka-cho, all of Nishinomiya-shi, Japan Filed May 21, 1958, Ser. No. 736,863 Claims priority, application Japan May 23, 1957 1 Claim. (Cl. 185.3)

This invention relates to an apparatus for the manufacture of phonograph records, characterized by that a record forming material is put between upper and lower record stampers, which are heated by charging with electricity, and after said record forming material is trans scribed with sound track by pressing said stampers, the electricity is turned oh" and the record is cooled.

The object of the invention is to obtain excellent records without noise by using a simple equipment, wherein heating and cooling are speedy and easily performed as well as exact temperature control is assured, thus eliminating the heating boiler used in prior art.

In the prior art of phonograph records manufacturing, pressing cases of large heat capacity are provided on the backs of record stampers, which cases are heated by the supply of high temperature vapor. The heat is transmitted from the stampers to the record forming material put therebetween and sound track is transcribed in said material by heating and pressing said cases, then the supply of vapor is cut off and cooling water is supplied into said pressing cases to cool the material through the stampers. Then the pressure is removed and a finished record is taken out. In this case, however, as the pressing cases of large heat capacity are by turns heated and cooled, considerable amount of high temperature vapor and cooling water is required, accompanied by considerable heat loss, in view of which a large type high pressure boiler must be provided. Other serious disadvantages are present since it takes a relatively long time for heating and cooling, with low production efficiency, and further it is difficult to maintain a constant heating temperature resulting in an unequal quality in the finished records, etc.

The present invention is proposed to eliminate such defects as above mentioned and its details will be explained with reference to an embodiment shown in the accompanying drawings, in which: FIG. 1 is a schematic side view of a record stamping equipment, with partial section thereof. FIG. 2 is a plan view of a record stamper.

In these drawings, two record stampers 2, 2 made of iron, nickel or alloys thereof each having a transcribed sound track 1 on the opposite sides, are arranged on upper and lower sides, and on each back side of said stampers which is devoid of a sound track, electrically insulated layers 3, 3 are provided and reinforcing liners 4, 4 are placed against layers 3, 3. Water jacket blocks 5, 5 are positioned respectively against reinforcing levers 4, 4, and the blocks 5, 5 being fixed respectively to bed block 6 and moving block 7 of a press. One end of each of the stampers 2., 2 is mutually connected by a lead wire 8, and each other end of each stamper is connected respectively with each end of secondary line of a transformer 9, in which circuit, a variable resistance 1 is inserted in series.

The stamping equipment formed as above mentioned will be operated as follows.

At first, the record stampers 2, 2 are separated by operating the press, then a record forming material 11 is put on the recorded sound track 1 of lower record stamper 2, and by operating the press, the upper stamper is moved down to contact with the material 11, and during pressing said material, electric current is supplied to 3,039,139 Patented June 19, 1962 ICC the transformer 9 and low tension current is charged through the stampers 2, 2 to heat the stampers and, by the heat thereof, the material 11 is heated and softened, thus the sound track is transcribed thereon. Then the electric current is out 01f and the blocks 5, 5 are cooled by supplying water therein, and by moving the upper stamper upwards and separating it from the lower stamper, a finished record is taken out.

The following is an example of manufacturing of 7" phonograph record according to the present invention.

Nickel plates of 0.3 mm. thickness are used as record stampers, to which electric current of 1.6 v., 1200 a. is suppled in 3 seconds, and during which pressure of kg./cm. is applied in 2 seconds, then the current is cut off and the water jacket is supplied with cooling water in 3 seconds, and by operating the press, a finished record is taken out. Total time of operation is about 10 seconds per record, including the operation time of press.

On the contrary, when the 7" phonograph record is manufactured according to the prior art of steam heating process, vapor of 9-12 kg./cm. pressure is applied to pressing case in about 20 seconds, during which pressing is continued in 10-15 seconds at the pressure of 150 kg./cm. then the vapor is cut oif and at the same time, cooling water is supplied in 15-20 seconds to cool the case, and by operating the press, a finished record is taken out. Total operation time is 40-45 seconds per record, including the operation time of the press.

According to the invention, as apparent from above example, the record can be manufactured with higher efiiciency in Mt-Vs time of that of steam heating process in prior art, and as no boiler is needed, the cost of manufacturing equipment is considerably reduced, and as the record stampers themselves are used as resistance heating elements, the heat generated by electric current supply is directly supplied to the record forming material and effectively used therefor, and as the heat capacity of the stamper is considerably smaller than that of the pressing case, the heat loss accompanied by cooling is small, and further, as the temperature of record stampers can be easily adjusted by the electric current, the record forming material can be heated at the fixed temperature, thus noiseless, excellent and equal products can be easily manufactured.

In the above example, nickel plates of 0.3 mm. are used as the record stampers, however, for which iron or nickel plate of 0.3-1.0 mm. thickness may be used, and the electric voltage may be used as low as 0.2. v. and its vicinity, and as the record stamper is made thinner, so the heat loss is smaller because of its heat capacity being smaller, and the lower the voltage, the thinner the electric insulation may be made.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

A device for imprinting an inscription on heat deformable record forming material comprising a first bed block having means for conducting fluid therethrough, a first relatively thin highly conductive stamper die mounted on said bed block with an impression face exposed thereabove, a movable press, a second bed block mounted on said press having means for conducting cooling fluid therethrough, a second relatively thin highly conductive stamper die mounted on said second bed block with an exposed impression face, said press being movable with said second stamper die into cooperative pressing engagement over the heat deformable material disposed therebetween, and electrical means to supply low voltage high current to said stampers to heat the stampers instantly and to form an impression on the deformable material therebetween, said stamper dies being made of nickel plates of approximately mm. in thickness.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Wells Apr. 27, 1926 Joyce Nov, 2, 1926 Kosowsky Aug. 14, 1956 Daniel Dec. 24, 1957 

